Manufacture of soap products



Patented Aug. 14, 1945 MANUFACTURE OF SOAP PRODUCTS Floyd E. Joyce and Erik J. Lindhardt, Des Moines, Iowa, assignors to National By -Products, Incorporated, Des Moines, Iowa, a corporation of Iowa No Drawing. Application October 23, 1943, Serial No. 507,482

8 Claims.

Our invention relates to the treatment of soap and is particularly concerned with a new and useful process for the preparation of granulated soaps or soap products.

In our co-pending application, Serial No. 473,688, flled January 27, 1943, now Patent No. 2,332,727, issued October 26, 1943, we have disclosed a method of preparing soap products involving the subjection of a hot, uncrutched, undiluted, fluid to semi-fluid soap, having a moisture content between 6% and 30%, to a certain mulling and mixing action. In the preferred embodiment of our aforementioned invention, the mulling and mixing action was accomplished by means of an apparatus comprising a vessel or trough having heavy rotors carried on, a revolving cross-head, said rotors being supported so as to run slightly above the bottom of the vessel or trough, the cross-head being adapted to be revolved slowly together with the rotors: The hot, uncrutched, undiluted, fluid to semi-fluid soap was introduced directly into such apparatus and was subjected to the action of the heavy rollers therein until the soap hardened and was broken up into particles.

Our prior invention brought about certa n important improvements in the preparation of granulated or relatively'finely divided soap products, both from the standpoint of the character of the products themselves and the properties thereof and from the nature of the procedural steps involved in the preparation of said roducts.

We have now found, in accordance with our present invention, that relatively finely divided or granulated soap products of excellent properties may be made without the necessity of initially starting the process with a hot, uncrutched and undiluted, fluid to semi-fluid soap. We have discovered that the intensive mixing and mulling,

treatment described in our aforementioned patent is applicable to the treatment of pastes or relatively thick, viscous masses prepared from previously finished or prepared soap chips or the like, the treatment being carried out without any necessity for the application of heat or of cooling.

In general, our present method of preparing granulated soap products comprises converting cold dry soap chips or the like, containing preferably a relatively high content of anhydrous soap, for example, from about 80% to 100%, into a relatively heavy paste with water, and then subjecting the resulting paste to the action of mulling rotors in the same type of apparatus which is described and encompassed in our aforemen-- tioned patent, the action of the mulling rotors being carried out until the soap product has been converted into a granular product.

In an illustrative embodiment of our invention, conventional soap chips, such as those prepared from a grease or tallow base, are placed in the mulling or mixing machine and enough water, in the usual case approximately 20% to 25% by weight, is added to convert the said soap chips into a relatively uniform paste. The rotors are then set into operation at a speed of approximately 25 revolutions per minute and the intensive mixing and mulling is carried out for approximately 10 minutes, in the usual case, at the end of which time the entire mass of soap crystallizes and disintegrates into granules.

If it is desired to make a filled soap product or a modified soap product by the addition of various ingredients such as alkaline salts, tillers, essential oils, perfumes and the like, or if it is desired to add water-softening chemicals such as soda ash, trisodium phosphate, tetrasodium pyrophosphate, sodium tetraphosphate, hexametaphosphates or the like, such can be very conveniently added to the soap paste prior to the subjection thereof to the action of the muller rotors.

The character of the intensive mixing, squeezing, rubbing and sliding action of the mullers and, in general, the type of the mixing action thereof, including the effect of the plows, where such may be employed, has been thoroughly described in our aforementioned patent and, since the same equipment may be used in the carrying out of our present process, a detailed description of such apparatus does not appear to be necessary. While we prefer particularly to employ apparatus such as described in our aforementioned patent, we may use other types of mullers or the like.

As we have described in our patent, the muller wheels should be supported above the bottom of the vessel or trough, in which the soap paste product is disposed for treatment, a small distance, for example, about A; to 1% of an inch. This insures the formation of a granulated product and avoids a grinding action which would produce a powder. It will be understood, in this connection, as described in our patent, that a soap which is in too finely powdered form tends to lump and agglomerate in water and thus remain for a long time undissolved. Furthermore, the fine dust becomes suspended in air and is hazardous to health, causing eye and nose irritation. By the adjustment of the muller wheels above the bottom of the vessel or trough, as we have described, the portion ofso-called fines or powdered soap particles in the finished product is materially reduced.

The muller rotors may be rotated at varying speeds, in general, speeds of the order of 5 to 50 revolutions per minute being satisfactory, approximately 25 to 30 revolutions per minute giving particularly good results in ahnost all cases.

It will be understood that after the mulling and mixing treatment of the soap paste is completed, the product may be discharged from the mullin apparatus and'passed through sizing screens, if desired, and then packaged without further v processing.

As we have previously indicated, the soaps which maybe treated in accordance with our invention are preferably initially somewhat sub-divided so as to be in chip or similar form and their characteristics and compositions may be of widely varying character. Thus, for example, they may be of a titer within the range of approximately 25 degrees C. to approximately 43 degrees C. The fatty acid or fatty acid base of the soaps may be derived from various sources, as, for example, greases, tallow, vegetable and animal oils of various character and mixture thereof. Such soaps may also contain additive ingredients of varying character as, for example, rosin.

While our present invention is particularly concerned with the preparation of granulated soap products containing a high percentage of soap, for example, at least 50% by weight of anhydrous soap and preferably from 60% to 80% and more, in its broader aspects it also encompasses the production of soap products having materially lower soap contents. Thus, for example, products may be made containing, for example, of the order of to 25% of soap, or somewhat more or less, the balance being fillers alkaline materials, and the like. As we have stated, however, the more important aspects of our invention relate to the production of soap products containing a high content of anhydrous soap.

It will be understood that the granulated soaps made in accordance with our invention may be converted to products of materially lower density than that of the granules themselves. Thus, for example, the granules may be passed through rolls, as described in our patent, in order to convert the same into thin flakes. In the light of the foregoing description, it will be seen that our present invention brings about certain important advantages in the soap making art including, among other things, the provision of a very rapid method of conversion of soap products to granulated form in a simple, efllcacious manner with low equipment investment; high yields of granulated product are obtained without the production of excessive amounts of fines or dusts; thorough incorporation of alkaline materials, water-softening salts, and the like, may be effected so that the final soap product comprises an intimate mixture of the component ingredients thereof, thereby obviating the disadvantage of that separation or segregation occurring such as is characteristic of simple mechanical mixtures of soap and such salts; the ability of the process to handle the treatment of soap products of widely difierent formulae; and the avoidance of the necessity for using either heating or cooling procedures.

While the invention has been described in detail, it will be understood that various changes may be made without departing from the spirit and the guiding principles of our invention. It

will be understood that the full scope of the invention is not to be limited other than is set outinthe claims.

What we claim as new and desire to protect by Letters Patent of the United States is:

1. A method of making a granulated soap product which comprises providing a soap in paste form and subjecting said soap, at not substantially in excess of room temperature, in a vessel having mulling rotors carried on a revolving cross-head therein, said rotors being supported so that they run slightly above the bottom of said vessel, to the action of said mulling rotors while the same are slowly revol ng, the action being continued until the mass is broken down into granules due to the action of said mulling rotors.

2. A method of making a granulated soap product which comprises providing a soap in the form of chips, adding water thereto to form a pasty mass, and subjecting said soap, at not substantially in excess of room temperature, in a vessel having mulling rotors carried on a revolving cross-head therein, said rotors being supported so that they run slightly above the bottom of said vessel, to the action of said mulling rotors while the same are slowly evolving, the action beingcontinued until the mass is broken down into granules due to the action of said mulling rotors.

3. A method of making a granulated soap product which comprises providing a soap in chip form, adding approximately 20 %-25% water thereto to convert said soap into a pasty mass, and subjecting said soap, at not substantially in excess of room temperature, in a vessel having mulling rotors supported so that they run slightly above the bottom of said vessel, to the action of said mulling rotors while the same are slowly revolving, the action being continued for a few minutes until the mass is broken down into granules due to the action of said mulling rotors.

4. A method of making a granulated soap product which comprises providing a soap in paste form, adding modifying ingredients to said paste, and subjecting said paste, at substantially ordinary room temperature, in a vessel having mulling rotors supported'so that they run slightly above the bottom of said vessel, to the action of said mulling rotors while the same are slowly revolving, the action being continued untll the mass is broken down into granules due to the action of said mulling rotors.

5. A method of making a granulated soap product containing a major proportion of soap from a soap product in divided form, which comprises adding suilicient water to the soap product to convert the same into a paste, and subjecting said paste, at not substantially in excess of room temperature, to the action of slowly revolving heavy rollers in a vessel until the soap product solidifies and is converted into granules.

6. A method of making a granulated soap product from a soap product in chip form which comprises adding sufficient water to the soap chip product to convert the same into a paste, and subjecting said paste, at not substantially in excess of room temperature, to the action of heavy rollers in a vessel until the soap product solidifies and is converted into granules.

7. A method of making a granulated soap product containing from about to soap from a soap product in chip form which comprises adding approximately 20% to 25% of water to the soap chip product to convert the same into subjecting said paste, at not substantially in ex- 10 cess oi room temperature, to the action of revolving heavy rollers in a vessel until the soap product solidifies and is converted into granules, said rollers being spaced from about to about of an inch above the bottom of said vessel and revolving at about 5 to about 50 revolutions per minute.

" FLOYD E. JOYCE.

ERIK J. LINDHARDT. 

